Java EnumMap equals()
Java EnumMap类的
equals()方法用于比较两个映射是否相等。此方法基本上将传递的对象与此EnumMap对象进行比较。
语法
public boolean equals(Object o)
参数
o -要与此地图进行相等性比较的对象。
返回
如果指定对象与此地图相等，则此方法返回true。
异常
NA
示例1
import java.util.*;
public class EnumMapEqualsExample1 {
public enum Tutorial {
CSS, Python, PHP, Java, Javascript
}
;
public static void main(String[] args) {
EnumMap<Tutorial, String> new EnumMap<Tutorial, String>(Tutorial.class);
EnumMap<Tutorial, String> map2 = new EnumMap<Tutorial, String>(Tutorial.class);
map1.put(Tutorial.CSS, "1");
map1.put(Tutorial.Python, "2");
map1.put(Tutorial.PHP, "3");
map1.put(Tutorial.Java, "4");
map2.put(Tutorial.CSS, "1");
map2.put(Tutorial.Python, "2");
map2.put(Tutorial.PHP, "3");
map2.put(Tutorial.Java, "4");
System.out.println("Map1:"+map1);
System.out.println("Map2:"+map2);
boolean equal = map1.equals(map2);
System.out.println("Map1 and Map 2 are equal: "+equal);
map2.put(Tutorial.Javascript, "5");
equal = map1.equals(map2);
System.out.println("Map1 and Map 2 are equal: "+equal);
}
}
输出:
Map1:{CSS=1, Python=2, PHP=3, Java=4}
Map2:{CSS=1, Python=2, PHP=3, Java=4}
Map1 and Map 2 are equal: true
Map1 and Map 2 are equal: false
示例2
import java.util.*;
public class EnumMapEqualsExample2 {
// create an enum
public enum Days {
Monday, Tuesday, Wednesday, Thursday
}
;
public static void main(String[] args) {
EnumMap<Days, String> map1= new EnumMap<Days, String>(Days.class);
EnumMap<Days, String> map2= new EnumMap<Days, String>(Days.class);
map1.put(Days.Monday,"1");
map1.put(Days.Tuesday,"2");
map1.put(Days.Wednesday,"3");
map2.put(Days.Monday,"1");
map2.put(Days.Tuesday,"2");
map2.put(Days.Wednesday,"3");
System.out.println("Map1:"+map1);
System.out.println("Map2:"+map2);
boolean equal = map1.equals(map2);
System.out.println("Map1 and Map 2 are equal: "+equal);
map2.put(Days.Thursday,"4");
equal = map1.equals(map2);
System.out.println("Map1 and Map 2 are equal: "+equal);
}
}
输出:
Map1:{Monday=1, Tuesday=2, Wednesday=3}
Map2:{Monday=1, Tuesday=2, Wednesday=3}
Map1 and Map 2 are equal: true
Map1 and Map 2 are equal: false
